Posted
by
ScuttleMonkey
on Tuesday November 08, 2005 @08:35AM
from the not-just-hot-air dept.

Sterling D. Allan writes "After 10 years of prototyping, wind tunnel testing, patenting, and tweaking, Ron Taylor of Cheyenne (windy) Wyoming is ready to take his vertical axis wind turbine into commercial production. Design creates pull on the back side contributing to 40%+ wind conversion efficiencies. Because it spins at wind speed, it doesn't kill birds, and it runs more quietly. It also doesn't need to be installed as high, and it can withstand significantly higher winds (can generate in winds up to 70 mph, compared to ~54 mph tops for propeller designs). Generating costs estimated at 2.5 cents per kilowatt-hour, putting it in the lead pocket-book-wise not just of wind and solar, but of conventional power as well. Production prototype completion expected in 5-7 months."

Whilst this has a large amount of vapourware about it they do at least have working prototypes. Given the high profile of windfarms in the UK I can see more efficient designs being taken up in a big way. It may be a bit early to bet the farm but I wouldn't be surprised to see these on an off shore site near you in the next few years.

There are at least two types of verical turbines. In one type [wikipedia.org], "The Darrieus type is theoretically just as efficient as the propeller type, but in practice this efficiency is rarely realised due to the physical stresses and limitations imposed by a practical design."

In the other type [wikipedia.org], "Because they are drag-type devices, Savonius turbines extract much less of the wind's power than other similarly-sized lift-type turbines."

I only skimmed the TFA but the pictures make it look an awful lot like a Savonious rot

This has been an epic last few weeks for the ability of crackpots to get pseudo-science posted on here. I suspect its actually just a game the editors are playing -- trying to see how riled up they can get everyone. I suppose, though, its possible its just another example of why Slashdot either needs new editors or story moderation.

How is this open source? Pictures are not shown because it is patent pending and every other paragraph mentions something about the patents, at one point proudly mentioning that they are sufficiently broad to make an attorney happy (because they'll mean lots of work for the attorney?).

But my question is, if it has a patent pending, why don't they publish? I thought that the whole reason for patents was to encourage people to publish their inventions. If the patent is pending, what's the risk?

Right- the AP picked up a story from the Casper Star-Tribune, which then got reprinted by the Seattle Post-Intelligencer, CBS News, Yahoo News, etc. That story was basically coverage of a press conference. I don't imagine there's a whole hell of a lot to cover on any given day in Cheyenne, so of course they'd be there. The fact remains that they don't have a production prototype, and haven't shown anything, so for now they're all talk.

I guess you didn't notice that the story was also run by CBS News and Yahoo News, among other mainstream organs.

They're all just regurgitating the same story/press release that originated at the Jackson Hole Star Tribune and was passed along to the AP. All this is is an advertisement for venture capital, the same as the last couple you submitted. Both you and Slashdot should be ashamed at running these adds. as if they were news.

While vertical axis wind generators aren't new - the Soviets utilized vertical designs for the most part - this design is. Wind power usually isn't practical or environmental for large-scale deployment (land usage/kW is too high), and I expect this design won't change that, but it could make wind an even better choice for microgrids [wikipedia.org].Shame the article reads like Yet Another Slashvertisment (someone wants venture capital I guess) - I'd like some more details.

This design isn't new. It's bunk. As he describes it, it's a Savonius windmill, which is nothing if not inefficient.

Although your comments about microgrids are very apt. And since what we truly need in this world are microgrids (encourage conservation of energy, reduce fossil fuel use, provide energy to Africa), I'm very excited about wind's possibilities in this arena.

(Which is why I just started a PhD. in solar and wind microgeneration cells.)

Thanks for the info. I had never heard of Savonius windmills before -- or at least not heard the name. I've actually seen one before though, but not for any practical purpose: one of those annoying moving-lawn-ornament type things.

In case anyone else is interested in what a Savonius windmill is, there's a page with a little simulation of one here [picoturbine.com]. I think they're selling something (model turbines maybe?) although I didn't really check it out.

I have to wonder though whether one of these is really as efficent as a propeller-type windmill, given that a propeller type one can alter its blade pitch and keep the rotational speed relatively constant in different wind speeds. Is there a way to do that with a Savonius design? It doesn't seem like the airfoils are really anything that you could easily change in flight.

I'm not sure if it's true, but I once heard an interesting factoid about Dutch-style propeller windmills, and how they were among the first mechanical devices to implement a "feedback loop"; you have a tail rotor mounted perpendicular to the main rotor, which drives the mechanism that orients the windmill. If the wind isn't blowing at the mill directly from the front, it causes the small rotor to turn, turning the mill into the wind. When the mill is pointing in the right direction, there's no wind on the small rotor, so it stops. Pretty brilliant, for the 17th or 18th century.

I have to wonder though whether one of these is really as efficent as a propeller-type windmill, given that a propeller type one can alter its blade pitch and keep the rotational speed relatively constant in different wind speeds. Is there a way to do that with a Savonius design? It doesn't seem like the airfoils are really anything that you could easily change in flight.

From my readings, and as a pilot, I can hazard a guess that this is because of the enormous complexity both in manufacturing and in mainte

Just looking at the prototype from the article, it looks to me like they have "inlet guid vanes" which would direct the incoming air so that it hits the rotor blades at the correct angle, so there would be no need for variable angle of attack (as there is with propellers...).

There have been wild claims for savonious rotors for many years. One, in Mother Earth News back around 1976 or thereabouts claimed 6 kw output for a machine made of two split oil drums, around 3 feet in diameter and 6 feet tall -- that's 18 square feet of frontal area. Power goes with the dimension squared (for circular frontal area) and speed cubed, so, double the dimension (radius, diameter), you see 4 * the area and thus 4 * the power available. Double the speed and you see 8 * the power available, all given some constant (never happens) coefficient of conversion.

Roughly, power = 1/2 * rho * v^3 * a * k * cwhere rho is mass density of air, v is windspeed, a is area, and k converts all units to power units. If you use square feet and feet per second as units, and 0.00238 slugs/ft^3, then you need to know that 550 ft-lbs/second will convert to horsepower. "c" is the conversion coefficient, typically around 0.25 for a good bladed rotor, probably closer to 0.1 for a savonious. I have built and seen rotors that did better than 0.3. Factor in loss due to generator power conversion, transmission line losses, etc, and things go downhill from there.

In general, there is a Betz limit that says, mathematically, that the most you can ever harness from a fluid flow such as wind is 59%, though there are suspected ways around that. When these people deride "tip speed ratio" they are giving up the fact that, when you can travel faster than the wind, as does the outer regions of a bladed turbine, you have the opportunity to generate more power due to the lift-to-drag ratio of high aspect ratio blades (wings) providing lots more torque than you would get by mulling along at around the same speed as the wind. Take a look at those multibladed farm water pumpers. They have a tip speed ratio rarely greater than one, and their conversion efficiency is fairly low. They're good for high starting torque to lift water. In electrical generation, you don't worry about starting torque because generators don't "kick in" till you're flying fairly fast. There is one aspect to the claims in the granted patent: he adds external "airfoils" to direct more wind into the central sevonious rotor, speaking of which, it's hard to tell from the pictures, but he may miss one nice point about generalized savonious rotors: the gap in the middle. If he closed that, he loses a lot due to the "airfoil" effect of the retreating (driving) blade directing some of the airflow through the gap into the advancing (dragging) blade (cup if you like).

In some sense, what he claims in his patent is well known in prior art. It's a lot like those dumbass patents the USPTO is granting these days for stuff like "one click", or "shopping carts" -- those folks in the USPTO never go outside and smell the roses. The patent presently granted can be stomped all over with photos from even ths us department of energy archives.

Dumb stuff like this comes along all the time. I don't think this is the work of a charlatan; rather, it really appears to be the work of an honest, but not well educated fellow. Clever, but not original or novel (novel to him, not to the rest of the world). Too bad every time someone comes along with a perpetual motion machine or something close (really cheap energy), they have to slam everything else that's already out there.

An earlier poster here commented on the apparent low quality of the website that printed the press release. Too bad about that. I'm reminded of the somewhat childish but good hearted efforts, long before the web, in the late 70's following the huge gas pump crisis in the U.S. Everybody and his uncle started printing journals, whatever, including The Mother Earth News. Some of it was good, some of it was rubbish, but we all had a ton of fun doing it. Looks like what goes around comes around. Again.Jack Park

I'm sure you didn't mean it, but that's pretty patronising. People were making ingenious use of wind power long before the 17th century, for example the use of tacking [asianyachting.com] to sail against the prevailing wind. They only reason ideas like this seem simple to us is because we've had exposure to the creativity of previous generations.

Yeah, I was quite shocked to see this. Even more shocked to see that he has patents for it. I worked on a vawt for awhile. There are about a 1000 different variations online by diy'ers. Savonius originally patented something that looks essentially identical to this device in the 20s! From my experience its great in areas where you have a low constant wind. Tip speed sucks, but you can get more torque with this device. It works great in an area with lots of flat like where I live (Indiana). I believe it was originally designed to be used to grind grain on farms.

yes and no. the best wind generator is the vertical axis generator. it removes a significant amount of complexity and can be easily made from junk lying around most farms. 55 gallon drums cut in 1/2 make the blades easily(plastic ones are best) and a belt/pulley system to a car alternator makes an inefficient version, you can make a highly efficient version that will produce usable power at only 6-8mph winds if you make your own coil pack and greater your permanent magnet stators with the surplus high power jobbies available most anyplace.

I helped erect one in northern Michigan, it can generate 106 watts in the calm days from the natural constant wind going up their hill and generated almost 1.8Kw peak during a storm before it threw the belt off.

no complex wiring to couple a spinnable generator to the power coming down, dirt simple and works at only 40 feet off the ground. if you paint them white they look pretty nice and can be built in a day if you don t build the alternator yourself.

personally I am surprised there are not more of them compared to the highly complex spinning blade setup that must pivot to follow the wind.

Who cares if the more complex is more efficient, if I can build 20 of mine for the price and effort of 1 typical wind generator I'll end up ahead.

These things don't look like they scale up very well. Wind power is all about swept area - or in this case profile area. To get more power you need more volume of air moving past. How does this type of design scale? Or is it limited to home use?

it scales vertically. we built one with 6 55 gallon drums. 3 on the lower tier 3 on the upper tier cut in a way to have 6 blades per tier. all attached to the central shaft using a thrust bearing at the top and botton and then to a pulley that turns the rotor on a home built alternator at 3 times the rpm that the windmill is spinning at.

works great. put another next to it and now I get 2X the power generating capacity. add 3 I get 3 times the power generating capacity. that's the neat part 1 windmill does not slow down all the wind and scaling up works perfectly when you think of it in a multiples instead of one giant windmill.

a small village trying to be seld sustaining could create a farm of these and generate power. wind is not the only source you need, you have to couple it with solar. because the days it's not windy it's usually very sunny. and all of it needsto go into a storage system.

Typically simpler = better. because you can make more of them to compensate for the lack of efficiency that highly complex may or may not give you.

that's the problem with alternative energy, too many people make it complex as hell and scares the realy users away from it. Anyone can create a hang out your window solar heat collector that works fantastically well for about $19.00 in parts and a little time gluing, nailing and painting. But you only see the hyper expensive requires engineers to install systems advertised or talked about. same as solar electricity. you can buy your solar cells for pretty darn cheap, you do not have to pay $5000.00 per panel for new state of the art stuff.

Same as you do not need to be a aeronautical engineer and able to carve an airfoil propeller to make a good working windmill.

Your points are true only on a small scale, they fail on anything large.

All windmills slow the wind. If you add a second windmill, and the wind is blowing such that it would go from one to the next (in absence of any windmills/trees/buildings), the second windmill will see slower wind than the first, and thus generate less power.

All windmills create turbulence zones around them, mostly downwind. This too decreases the efficiency of the windmills downwind.

Well, here's blowing a razberry at you, kid. Are you a votary of the oil lobby?

Land usage / kW for wind turbines is NOT too high. You only actually need half an acre/MW. The rest of the land is for wind easement, and you can carry on farming/horticulture without much interruption on it. And this is true only for Europe and N. America.

In developing countries, windy land is mostly arid, mountainous, or coastal - nothing much grows there.

Large scale wind developments are economically viable. Wind gets the minimal of governmental support, and look at how it's growing. Lots of free tools are available on the web to see it for yourself - various HAWT models, various sites around the world.

Distributed development of wind power projects over geographically distant areas can theoretically reduce intermittency, which is the usual FUD against wind these days. Avian kills are another FUD: what is the extent of ecological damage being caused by your conventional power plants? What is the submergence being caused by hydropower?

About TFA, well, there is a huge amount of development taking place in both HAWT and VAWT technologies, with competition between generator and/or drivetrain philosophies./. can randomly mention anything - maybe somebody is fishing for funny comments.

HAWTs have a distinct advantage of exploiting the swept area and the power law index by increasing rotor diameters (blade lengths). VAWTs may evolve into simple designs without much need for regulation - there are some that offer inbuilt speed regulation by design. They can generate at any wind speed that the supporting structure can withstand. However, I am yet to see VAWTs catching up with HAWTs having rated capacities of decade-old standards.

Some of the VAWTs of the type in TFA can be well suited for use in defence installations - I've myself suggested one design to a defence research official for distributed, arctic-condition, radar/thermal/sonic neutral generation needs at the world's highest battlefield. I don't know if they have researched it further, but they won't tell:-)

-clueless

Disclaimer: I work for a wind turbine manufacturer. However, I have stayed with them because I like the industry.

if the downwind blade is travelling at windspeed, it is generating no force (and admittedly killing no birds who are flying with the wind, ie balloons). But, that implies that the upwind blade is travelling at twice the windspeed, relative to the wind.

So that little argument is rubbish.

Actually, the whole article is not too bad overall, we certainly see worse in real papers (eg the Guardian's coverage of that hydrogen atom fraud).

I think the idea is that it doesn't move as fast as a propeller: From TFA:

One of the primary environmental drawbacks of the propeller wind turbines is that they kill birds. The tips of the blades spin much faster than the wind speed, chopping through the air sometimes at speeds of 200 mph. The birds generally just don't see them coming.

The TMA vertical axis design flows with the wind, at the speed of the wind. "It looks like a building to the bird," said Taylor. "We've never seen a dead bird at our te

Another obvious advantage of this design is that unlike a propeller, you don't have to turn them around when the direction of the wind changes...

A couple of years ago I talked with an engineer friend about this when we got on the subject of alternative energy. This isn't a new idea of course, variations have been used above chimneys [fluesystems.com] for a long time for instance. He told me then about the large number of advantages to this design. I don't remember if I asked him the question that pops up in my head now - why did the propeller design become the norm?

"Another obvious advantage of this design is that unlike a propeller, you don't have to turn them around when the direction of the wind changes..."

Of course, turning turbines around has been a solved problem since forever. The disadvantage of vertical turbines is that the wind is so much faster at the top than the bottom, which makes half of the turbine essentially useless.

That is because airospace engineers are the main designers of these kind of machines. They know propellers, have all the systems to calculate what is possible with it, and through old designs of windmills (from 1400AD or even earlier) the principles pretty much stayed the same.

Modern propeller turbines use lift to generate torque and efficiency scales up with propeller length. Verticle turbines which use drag (as the one in the article does) are not as efficienct to begin with, and their efficiency does not scale as you make them bigger. This is why the engineers don't make modern large scale wind turbines out of them.

Old windmills used wind drag to generate torque. Modern wind turbines use lift to generate torque. Saying the principles are the same is like comparing a glider to fighter jet.

A lot of it has to do with materials. VAWTs suffer from two notable stresses that are inexistant on HAWTs. 1) centripital forces and 2) vibration.

1) These things spin *quickly*. Far faster than the windspeed. Now, that's not so much a problem in a propeller blade because all the mass is on the inside and the blade happens to be strongest here, too. But on a VAWT, all the mass is on the outside, meaning that there is a significant amount of energy stored as they spin round and round. This pull can quickly destroy the windmill, and apparently has caused a couple deaths (Or so I have read in the windmill forums. Caveat reader.).

2) Because of the way the VAWTs spin, the mill is subject to pulsing as the blades change their angle of attack and speed with respect to the wind. Of course, this is reduced by having more blades which are thinner, (the ideal propeller being made out of an infinite number of infinitely thin blades) but the materials have limits and it seems that 2, 3, and 4 blades are all we can reasonably do. So the pulsing motion fatigues the support and can lead to failure.

HAWTs don't suffer from these problems, although they do have other problems-- such as torque applied by gyroscopic precession, torque applied by higher windspeeds at the top of the mill than at the bottom, orientation into the wind-- but they don't seem to be as difficult to overcome as the VAWT ones.

Apparently, this thing can handle going with windspeeds of over 154, while props fall must be braked or they'll fall apart. This likely has to do with the materials used.

Also, the wind-tunnel testing gave them a number of 2 blades.

That's the reason this _is_ news. This guy was able to overcome the inherent engineering problems with VAWTs (which are more efficient, but more difficult to design without the failures you described). The Slashdotters may think this is funny, or stupid, but...

It occurs to me that every time a new non-software technology has been reported on slashdot, >50% of those who comment on it are near-psychotic in claiming it's bunk. Why is that?

Propeller designs have the advantage that the propellor is generating power in every part of it's revolution. The blades of vertical rotors will always have a position in which they move against the wind, which causes drag or tricky aerodynamics at best. My uncle already worked on machines like these back in the 80s, the aerodynamics of these machines are not so easy I think.

The blades of vertical rotors will always have a position in which they move against the wind, which causes drag or tricky aerodynamics at best.

Actually, the blades are always moving agains a relative wind. What's tricky about the aerodynamics is that the relative wind constantly changes as you go round the circle. The solution to this is to spin faster, so that the wind component which changes (the real wind itself) is small in comparison to the wind component which doesn't (the relative wind produced tang

The non-directionality is as much a problem as it is a boon. A propeller driven turbine will turn if the wind speed is great enough. As long as it is pointing intow the wind and there is wind, it will do useful work. The typical design for a vertical wind turbine stalls if the wind falls below a minimum threshold and is not self-starting: the device must be spinning to recieve torque from the wind. In areas where there is a high, constant wind, this is not that much of a problem, but if the wind is high

Now being the old fuddy duddy I am (at the tender age of 21) I'm obviously using an old and outdated definition for "ready for commercial production." See, the definition I'm using is one where the prototyping stage is over, and these things are being made in some factory and are about to be sold to companies/people. Now obviously not being up-to-date with the latest definitions, I was quite excited when I read it was ready, only to have my hopes dashed by the end of the summary.

Why don't you call us old-timers when you actually have a commercial product?

Actually, the term Production Prototype *usually* means the first version actually built by manufacturing (as opposed to a hand-built version by R&D)... so this suggests to me that they are pretty far along - they actually have a manufacturing facility in place, people trained, material lists finalized, procurement contracts, etc. Of course they could just be *calling* it a production proto...

Actually, the term Production Prototype *usually* means the first version actually built by manufacturing

I didn't know that. But even so, it's 5 to 7 months before the production prototype is even built, and they're claiming it's ready to become commercially available NOW. It isn't ready to become commercially available now. It might be ready in 5 to 7 months, but that isn't now.

From: http://www.windside.com/ [windside.com]"Windside works, when others don't, with gentle summer breeze and in a violent winter storm. It works, when others are in deep frost. Windside produces electricity at least 50 % more in a year than traditional propeller models. All the year round. Many things make it extraordinary. And therefore it gives the best value for the money."

Not sure what the differences might be. Winside apparently has been producing these vertical axis windmills for extreme environments for, they say, about twenty years. But they do seem costly. They use a helix type design for the blades, see: http://www.windside.com/products.html [windside.com]

What he's proposing is a Savonius windmill. A fancy aenometer. Which we already do much, much better with the Darrius approach. The maximum possible energy that we can get out of the wind is 59%. Savonius windmills are far, far less efficient, as they rely on drag, and not lift.

Of course, he claims that it works off of lift, which-- if his mill even exists in reality-- it probably does, but the fact that it only gets "a little" boost from lift means that it is almost completely drag based.

One problem that people have when visualizing a windmill is the question, "Why not do it like a paddle-wheel? Like on an old steam-boat?" Well, do you still see those old steam-boats tooling up the river and across the ocean. No? Maybe you should wondered why. It's because... surprise, surprise, it's less efficient.

Not to mention the ridiculous claims about hurricane/tornado proof design. And the centripital forces it's have to undergo at these speeds. (Real VAWTs tend to be able to spin at such high speeds that they are explosively dangerous.) And the torque exerted on the bearing coupling of a several story high building when there's 150mph of wind pressing on the top.

opensourceenergy.com seems to be nothing more than a shrewd attempt to make fun of the/. crowd, by pulling us all in to wow at the latest, greatest power generation technique that's going to revolutionize our world.

I was reading about this company a few days ago & I dug a little deeper because the info was sketchy.What I found (and this article leaves out) is that there are a few negatives that need to be considered.

1. To do maintanence, you have to take the entire sucker apart in order to get at the bearings.

2. Height: Wind speeds are not even across various heights. There is a serious potential for nasty stresses when the wind is going faster at the top of this turbine than at the bottom.

If not this particular company and technology, the prices they are giving are in line with most analysts' expectations.

Like a lot of other technologies, this one is going down in price in a predictable way. Check out the wind energy data [earth-policy.org] at earth-policy.org, especially that last figure.

The sector has recently been experiencing Hockey-stick growth [worldchanging.com] in investment. It's pretty much inevitable that this is going to be cheaper than coal- and likely cheap enough to make hydrogen for when wind is low. Cheap, guaranteed price, non-polluting.

Judging from nuclear's track record, it won't come close to wind. These turbines might not be the ones to put nuclear out of its misery- but wind certainly will play a large part (don't discount solar just quite yet).

For the sake of argument, let's believe the hype just for a moment. From TFA:...the approximate sixty claims between the two U.S. patents awarded and a third pending, and numerous international patents secured as well. "Our patent attorney is very pleased with how broad our patent protection is," Taylor said.

If the design is so revolutionary, more financially viable than conventional power, and better for the environment, then no doubt they'll make a killing financially whether they patent it or not, as th

This link is the nicest derivation I have seen online of Betz's law regarding the maximum effiency (16/27 ~= 59%) of any non-compressible mass flow capture device. At least the article doesn't claim to exceed it (40%, I think). But as for high drag-devices getting a better effeciency than a variable-pitch propeller? That sounds pretty suspicious.

On the other hand, if it can endure much higher winds than a prop installation, its OVERALL effeciency might be higher, because the energy in a mass flow is proportional to the cube of the wind-speed; so the 1% high wind speed tail of the distribution contributes a large portion of the total energy captured by the turbine. Of course, having a bit more REAL info would be helpful in determining if this is just slick FUD or something real. And when significant data is not mentioned, it does make one tend to think there is something to hide.

While what you say is technically correct, I think one can still call a force due to reduced pressure relative to the surrounding a "pull". Otherwise one could also argue that a vacuum cleaner doesn't suck - the "sucking" is just the outside pressure pushing the air to the inside, since the pressure in the inside has been reduced by pushing some of the inside air to outside through a different way.

The energy you can take from the wind is proportional to the area of the device, and the cube of the wind speed. Three-bladed wind turbines are tall and big because wind is faster higher up, and so they can sweep a huge area. A three blade arrangement is aerodynamically optimal, getting closest to the Betz limit of about 59% (not 20-30% or whatever the web page said).

Also, bird death is about 1 per turbine per year for current technology. This is about 9 orders of magnitude less than bird death from buildings/vehicles/airplanes etc., and that's not considering the enviornmental consequences on bird life of NOT using renewable sources...

Dumpy little vertical axis machines may have limited uses in isolated installation, and for revolving advertising, but they are not practical for large scale generation. The rotor of a modern 5MW wind turbine is about the same size as an athletics track. Imagine how big this vertical axis machine would have to be to match the wind capture of this. If the alternative is to have many small devices, there would be a very large number indeed: this carries costs of electrical interconnection, massive maintenance overhead from trillions of puny alternators and gearboxes, all of which was probably ignored in arriving at the 2.5 cents per kWh.

The only way to make money with this turbine is to be the poor guy's patent attourney.

I would like to call a halt to posting links from Open Source Energy. The site is run by crackpots and kooks who espouse completely insane ideas that have absolutely no basis in reality. It takes about 5 minutes of browsing for any reasonable person to determine this.
Promoting this site is bad for slashdot. I do not joke when I say that posting links to this site is no better than posting links to some "intelligent" design site about new theories of evolution.

I am skeptic; it still looks like a meatgrinder to me. O.k it does not look like the propeller desigh that chops the bird, but when that thing is spinning at speed I am sure it pets the bird in the back as gently as a bud hits you with 50mph windspeed from the back....

just a visual observation, and probably they threw some chickens into their grinder before they claimed that.

Besides being an asshole critic, I really appreciate the aspect of renewable energy paired with not being a traditional meatgrinder.......

fact: did you guys know that costa rica is only using wind and water power? In fact we produce as much from these sources that CR exports energy to neighbouring countries; clean energy. In fact, while still considered a developing country, electricity coverage is the best in central AM, technically you have electricity everywhere. For US/European readers it is probably normal, but when you drive around in Panama/Nicaragua you canappreciate grid coverage here.

OK, water energy creates some mess with the environment in some cases especially when you have wetlands, because dams can affect these in a bad way, but still better than burning coal or radiating, etc.

The first in that list featured complete crackpot pseudoscience. The second seems to be of dubious scientific merit. A quick look at Mr. Allan's website [pureenergysystems.com] shows they are involved with a number of other areas of pseudoscience (or to put it less kindly, scientific hoaxes) such as "magnet motors" and "zero point energy" (as an energy source). That together with the two other submissions he's made leads me to doubt the validity of the information in these "stories". The main problem, however, is that these are not balanced informative articles, but rather they seem to be little more than ads seeking venture capital. Furthermore, it looks like Slashdot is soon to become little more than a mouthpiece for opensourceenergy.org [opensourceenergy.org] at this rate.

Shhhh! I'm in the process of drafting an article about my Open-Source, DRM-enabled, Rootkit Deployable Space Elevator Control Module complete with Socket-F support and Carbon Nanotube flux control. It's cool. And it's 50% more efficient than anything being done today. The only thing holding me back is the RIAA and MPAA. . .

Windaus Energy [windausenergy.com] (Ontario, Canada) has developed prototypes of a vertical-axis wind turbine and are looking for places to install working demos.

From an announcement they sent out earlier this year:

Designed and manufactured by Windaus, this device and the attendant transmission system is the first three-vane helical concept to our knowledge. Some limited testing has been done by the company but no formal field-testing for commercial application has yet been completed.

The prototypes are mounted with the larger models on wheeled trailers.

The properties inherent to our design do not allow the outer edge of the vanes to exceed wind speed. They are virtually silent. They are not intimidating. The design relies on torque rather than speed, and many benefits are derived from this concept. Also, most of the "working parts" are housed at the base of the frame, facilitating easy maintenance and simple upgrades. Its operation mitigates many challenges facing conventional horizontal-axis turbines.

Specifications are available on their website, including output, torque, power output. As other people have pointed out, there are some disadvantages to this style of turbine, but there are also some advantages. It looks far more suitable for local micro power than mega wind farms.

This isn't a new idea. Vertical wind turbines like that [cat.org.uk] have been built before. They're not very good. A better vertical design is the Darrius parabolic vertical turbine. [slashdot.org] There used to be a few dozen of those at the Pacheco Pass wind farm, but they've been replaced with bladed units. Verticals have the advantage that all the equipment is at the bottom, but the side loads on the bearings are a big problem.

There are several hard problems in wind turbine design. One is that, for large wind machines, wind speed may vary considerably across different parts of the blade area. This produces huge stresses in the blade system. Aircraft propellers and hubs don't have that problem, so technology borrowed from aircraft props didn't quite work. That's been solved, but it took years to get past it.

A basic problem, one which this new design doesn't solve, is overspeed protection. Wind turbines above toy size must be able to deal with high wind conditions safely. Some turn sideways; some turn upwards; some feather the props. Brakes aren't enough. There's no way to feather or turn this new design. Even small turbines [realgoods.com] need, and have, overspeed protection.

There are lots of wind machine designs that more or less work in a small size, but don't scale up to the point where they're worth building. There's a square law; double the blade length and get four times the energy out. So big turbines beat out little ones, once ths scaling problems are solved. Wind turbine size has been creeping up since the 1970s, from about 50KW to a few megawatts.

A 1.5 MW unit [energy.gov] was built in the 1940s, but it suffered a bearing failure within a year, then a loss of blade accident which threw a blade 700 feet. Only in the past decade have reliable wind machines in that size range [gepower.com] been produced in quantity. With 2800 of their 1.5MW units installed, General Electric can be said to have solved that scaling problem.

Yes, moving parts can always kill a careless animal of course, but I think their point was that this is easier to spot and looks like a building, so it is less likely that a bird flies into it. Nice, but from what I have heard it is actually very rare that propeller wind turbines kill birds either.

As silly as that sounds it is true...About six months past I read in a German paper that in the North where the windmill parks have changed the local climate (http://www.msr.uni-bremen.de/werner/rw/RWOffshore.htm [uni-bremen.de] not the real article). Essentially the windmills act like a wind dam and that changes the weather on nearby beaches. I think what the report said is that the beach received more sunlight than it usually would.

I'll be honest, I really have to wonder about the whole windmills-killing-birds business. It always gets dragged up, but does anyone really know how many birds those propellers actually kill? I'm willing to bet it's very low; I also suspect way more birds are killed by flying into vehicles on the highway, or into the sides of highrise buildings (I had one kamikaze into my house last week, and that's not even a high rise).

The whole bird thing sounds like a convenient excuse invented by people who really oppose windmills because of noise or land use issues, but want a fuzzier, more PR-friendly excuse. The kill zone on a windmill is basically going to be the circle described by the rotor tips as they go through the air, so it's not a huge zone (as you get towards the center they're not moving as fast, tangentially) and at any given time it's not as if just flying into that ring would result in death, you'd have to be at a point at the particular moment in time when the blade moved through it. Last time I checked, birds don't hover, so you have two moving objects that would have to compete against some long odds to end up in the same place at the same time. Also, the turbines are noisy as hell -- something which is a legitimate criticism -- and I find it hard to imagine that birds wouldn't be scared off by the sound, air currents, and motion. (Actually they wouldn't make a bad large-scale scarecrow over farmland...)

It always gets dragged up, but does anyone really know how many birds those propellers actually kill? I'm willing to bet it's very low; I also suspect way more birds are killed by flying into vehicles on the highway, or into the sides of highrise buildings (I had one kamikaze into my house last week, and that's not even a high rise).

If you google for Altamont Pass, you will find reports of what is apparently the most deadly wind farm for raptors in the U.S., and kills about 800-1300 birds of prey a year. It's the farm's location in this pass, a migration path for other birds which makes it a great home for many raptors such as golden eagles, that makes it high risk. It's the small size, tight placement, and old design of the turbines that turns that risk into actual dead birds.

Your intuition is correct here, in that this is a tiny amount compared to the number of birds that crash into windows of buildings in your average city. On a per-turbine basis, cell phone towers kill more birds.

However, many people have taken the issue seriously (the makers of the Altamont Pass turbines were taken to court to force them to reduce the danger of their farms to birds), people like my father who as a bird watcher and conservationist is most concerned about predator populations due to their important role at the top of the food chain. It turns out that these concerns are being addressed, and newer turbines are much less dangerous to birds, in particular raptors. New designs discourage perching on the supports (electrocution of perching birds being a problem apparently), and larger turbines with commensurately slower blades, have proven to reduce bird fatalities.

This is an issue I care about, loving as I do large animals that eat other animals, and I feel it is being duley considered and addressed. Wind farms do less damage to the environment than any other form of power generation other than solar, and kill fewer birds than the windowed office building that would be built to house the adiminstration for any form of power plant. That's no reason not to pressure the makers of the farms to continue to address bird deaths by improving their turbines, but it's also no reason to discourage the construction of wind farms. People who are against wind farms due to bird deaths have in my experience fallen into two categories: concerned environmentalists who aren't aware of the scope of the problem, and industrialists who just want to have something to put in the "negatives of alternative energy" column to line up with "releases more radiation than Three Mile Island on a normal day of operation" in the "negatives of coal" column so they'll both seem equally bad.

The turbines in Altamont Pass are known to kill quite a lot of birds, but this is partly because of their location in a bird migration path, and partly due to their design. The turbines there are of quite old designs, and in particular they are fairly small and fast rotating. Birds tend to have a hard time working out where they can and can't fly, and often get it wrong.

Modern turbine designs have taken these problems (and many others) into account and now kill very few birds - probably fewer than are killed by flying into electricity pylons. The main design changes are that they are much larger and slower rotating, so birds tend to judge the motion correctly and avoid them. Correct me if I'm wrong, but I think the Altamont Pass turbines are painted grey to reduce their visual impact against the sky, which also reduces their visibility to birds. Modern ones tend to be painted white, which makes them more visible.

On a recent visit to Denmark I was very impressed by the size and sheer number of turbines, turning gracefully, slowly and fairly unobtrusively. Occasionally there would be a small, faster-rotating one of an older design. These were noticeably more distracting and attention-grabbing - particularly in the peripheral vision (which after all is designed to look for rapid movement from predators). It's these older designs that have lead to most of the complaints from local residents, and understandably so.

Give me a modern turbine at the bottom of my garden any day - they are also virtually silent unlike their older cousins.

I love the huge turbines. I can see a medium sized wind farm from my home. They're beautiful to me because they represent pure, clean power. Not to mention, they're quite graceful in their movements and fun to watch.

The whiners who oppose them have their heads up their collective rear ends. Ask these people how they prefer to get their electricity and they can't answer you. Wind is ugly and kills birds. Solar is ugly and full of

To be quite fair to the grandparent, I've heard plenty of self-proclaimed environmentalists complain about aesthetics. Usually, though, they find some easier to argue position like "we have to think of the birds." Talking energy with them typically goes something like this:

Environut: Global warming is going to kill us all. We have to stop the evil oil companies bent of world destruction.

Engineer: The stored gas has equivalent chemical energy, yes, but it's release is dependent on the oxygen that can be supplied. The absolute worst case scenario is a really big fire.

Actually, the absolute worst-case scenario is a BLEVE, [blazetech.com] which you Do Not Want. When all of the factors are right, heat from a really big fire boils the LNG in its tank, overwhelming the pressure-relief valve. The valve sends up a shrieking tower of flame as it fails to keep up with the rising pressure, and everything that I'

Wind farms do less damage to the environment than any other form of power generation other than solar, and kill fewer birds than the windowed office building that would be built to house the adiminstration for any form of power plant.

This is a serious issue and needs to be addressed! How did solar power get away with causing so little damage?? I propose that all solar arrays be built slightly concave, and reflect most of the light they don't absorb (we don't want to reduce efficiency), creating giant death rays. This way we can ignite birds that fly through the kill zone and correct this serious deficiency.

In an unrelated issue, I'd also like some serious effort to be put into breeding chickens that can fly.

When I was in the Netherlands last year, I toured a large wind park north of Groningen. There, under the turbines, I saw a total of:

1 dead bird1 dead sheep

From this, we can deduce that wind turbines are equally as deadly to sheep as they are to birds. The 800-1300 sheep killed annually must make the Altamont Pass a bloodbath of truely horrific proportions.

But seriously, folks...

The Altamont Pass is a disaster which was produced by irresponsible economic incentives of the time which put up low quality turbines willy-nilly throughout California. Add to that the fact that many of Altamont Pass's are placed on angle-iron framework towers. These make them ideal nesting grounds--well, if one ignores the 30 m food processor out front. Modern towers take great care in leaving no place for avian habitation.

This park's would otherwise be just a regional problem, but, thanks to more animal-focused environmental groups, and the tabloids who eat up their press releases, that wind park is biting us over here in Europe in the ass.

Altamont Pass is, however, the only wind park on earth with this level of environmental impact. Nothing comes close in these regards. A substantially larger off-shore wind park off the coast of Denmark (Knoetby, I think) actually showed that the birds weren't scared off, but instead kept a distance of about 150 m from the equipment.

Where they near each other? I see two possibilities:1) Bird gets smacked by turbine blade beak-first into sheep's temple, killing it. The solution to this problem would be to sharpen the blades, so instead of striking the bird like a baseball it would cut them in half so the two halves would fall at normal speed to the ground.2) The sheep, being of a species well known for their craven cowardice and deep cunning (they only act stupid so as not to appear threatening), saw the dead bird, and upon considering the environmental implications, died of a heart attack. The solution to this problem is to give sheep internet access so they can research the problem themselves.

The Altamont Pass is a disaster which was produced by irresponsible economic incentives of the time which put up low quality turbines willy-nilly throughout California. Add to that the fact that many of Altamont Pass's are placed on angle-iron framework towers. These make them ideal nesting grounds--well, if one ignores the 30 m food processor out front. Modern towers take great care in leaving no place for avian habitation.

Just for everyone's convenience, here's a link [thewatt.com] to a page which shows the old-style tower and the new style and the obvious difference it would make in problems with perching and nesting. There's also the non-obvious scale difference, with the new larger one being much safer due to slower and thus easier to see/avoid blades. It also has per-turbine death rates for birds for various sites, with Altamont being much higher in raptor deaths than the others.

There was a problem with some early model wind turbines killing birds. Newer turbines may hit a bird once in a while, but are generally not so hazardous, or at least, that is my understanding of the situation.

I was at the UK national Bat conference this years and there were a couple of presentations on bat kills around wind turbines. It turns out that the strange noised attrach insects and therefore bats. Certain wind farms in the use, I forget which, are on migration paths for bats. There is a suggestion that they turn off the wind turbines come migration session.

Since bats are a key part of bug control, particularly in the US, you might want to think about protecting them,

The 1000 or so wind turbines on the North Sea coast of Germany near Holtgast have driven the water birds completely out of the area. The problem was not strikes, but the noise and perhaps visual disorientation. In any event over the last 10 years since the installation of the turbines the birds have abandoned the area.

does anyone really know how many birds those
propellers actually kill?

As a better question - Why does anyone care?

Stupid birds fly into things. We call that "evolution".
The birds without the sense to avoid rapidly moving
blades die, the ones with a bit more brains survive,
to produce offspring with the sense to avoid giant
poultry-processors-of-death.

We haven't banned cars, picture windows, or electric
lines yet - Why such a fuss over a technology that
has the potential to substantially reduce our

Put them on the corners of a skyscraper and the power is used only feet away from its generation.

Hmmm--this type of wind turbine could be perfect for the space on top of the planned Freedom Tower in New York Ciy that designers plan to install wind turbines inside that space. It would definitely be less threat to birds flying nearby and the noise level will be substantially lower, too.